Study Selection: All published randomized trials with a mean follow-up of 3 months or longer that tested antithrombotic agents in patients who have nonvalvular atrial fibrillation.

• 华法林的效应明显优于抗血小板治疗,同时资料显示，房颤病人的抗血栓形成治疗单纯降低卒中发生的效应强于单纯增高主要颅外出血的效应。